French translate

Fixed minor in French translation
Correction mineur de la traduction française
Best reading content once open admin menu

For a better reading of the section.main and once the sidebar is open, I
propose to reduce the size of the section.main and the width of the
sidebar (header) by a %. Some line enough.
Revert "Best reading content once open admin menu"

This reverts commit 17759f4e95e1a43ce33aa3b883875932d562a281.
Best reading content once open admin menu

For a better reading of the section.main and once the sidebar is open, I
propose to reduce the size of the section.main and the width of the
sidebar (header) by a %. Some line enough.